Two former Parramatta Eels players are accused of harbouring semi-automatic weapons and possessing more than half-a-million dollars in cash after dramatic arrests in Sydney's Centennial Park yesterday.

Sydney cop found guilty of refusing RBT

An off-duty Sydney police sergeant has been found guilty of using her rank and authority to avoid being randomly breath tested by a junior colleague.

Sarah Louise Johnston, 50, drove away from the RBT site without having been tested after a short conversation with the rookie cop at North Sydney on January 8, 2016.

Officer Tugcan Sackesen told the court he felt "intimidated" when Johnston said it would be a conflict of interest if he breath tested her.

"I was taught to respect authority and she's a sergeant of police and I'm a probationary constable with a year's experience," he said at the trial.

A jury on Friday found Johnston guilty of one count of doing an act with intent to pervert the course of justice.

The Downing Centre District Court trial before Judge Chris Hoy heard Johnston drank at least one schooner of beer while celebrating the new year with colleagues from North Sydney Police Station at two nearby pubs.

She was driving home to the Central Coast when she was pulled over at a random breath testing site on the Pacific Highway at Crows Nest.